/* Patent cards — professional catalog style */

.patent-card--pro {
  --patent-accent: #18181b;
  --patent-accent-soft: rgba(24, 24, 27, 0.06);
  --patent-accent-border: rgba(24, 24, 27, 0.12);
  display: flex;
  flex-direction: column;
  height: 100%;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border-default);
  background: var(--color-surface-card);
  box-shadow:
    0 1px 2px rgba(15, 23, 42, 0.04),
    0 8px 24px -12px rgba(15, 23, 42, 0.08);
  overflow: hidden;
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-base),
    transform var(--transition-base);
}

.patent-card--pro:hover {
  border-color: var(--patent-accent-border);
  box-shadow:
    0 4px 12px rgba(15, 23, 42, 0.06),
    0 20px 40px -16px rgba(15, 23, 42, 0.12);
  transform: translateY(-3px);
}

.patent-card--pay {
  --patent-accent: #2563eb;
  --patent-accent-soft: rgba(37, 99, 235, 0.09);
  --patent-accent-border: rgba(37, 99, 235, 0.22);
}

.patent-card--security {
  --patent-accent: #059669;
  --patent-accent-soft: rgba(5, 150, 105, 0.09);
  --patent-accent-border: rgba(5, 150, 105, 0.22);
}

.patent-card--privacy {
  --patent-accent: #7c3aed;
  --patent-accent-soft: rgba(124, 58, 237, 0.09);
  --patent-accent-border: rgba(124, 58, 237, 0.22);
}

.patent-card--other {
  --patent-accent: #52525b;
  --patent-accent-soft: rgba(82, 82, 91, 0.08);
  --patent-accent-border: rgba(82, 82, 91, 0.2);
}

/* Visual header */
.patent-card__visual {
  position: relative;
  padding: 18px 18px 14px;
  background: linear-gradient(
    165deg,
    var(--patent-accent-soft) 0%,
    rgba(255, 255, 255, 0) 72%
  );
  border-bottom: 1px solid var(--color-border-subtle);
}

.patent-card__visual::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--patent-accent);
}

.patent-card__cover {
  width: 100%;
  aspect-ratio: 4 / 3;
  max-height: 140px;
  border-radius: var(--radius-md);
  border: 1px solid var(--patent-accent-border);
  box-shadow: 0 4px 16px rgba(15, 23, 42, 0.06);
  overflow: hidden;
  background: #fff;
}

.patent-card__cover img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.patent-card__visual-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-top: 12px;
}

.patent-card__label {
  font-size: 0.75rem;
  font-weight: var(--font-weight-medium);
  color: var(--text-muted);
  flex-shrink: 0;
}

.patent-card__pub {
  font-size: 0.8125rem;
  font-weight: var(--font-weight-semibold);
  font-variant-numeric: tabular-nums;
  color: var(--color-text-strong);
  letter-spacing: 0.02em;
  text-align: right;
  word-break: break-all;
}

/* Body */
.patent-card__body {
  display: flex;
  flex-direction: column;
  flex: 1;
  gap: 8px;
  padding: 16px 18px 18px;
}

.patent-card__title {
  margin: 0;
  flex: 1;
  font-size: 0.9375rem;
  font-weight: var(--font-weight-bold);
  line-height: 1.5;
  color: var(--color-text-strong);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.patent-card__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  margin-top: auto;
  padding: 10px 16px;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-md);
}

.patent-card__cta i {
  font-size: 0.75rem;
  opacity: 0.9;
  transition: transform var(--transition-fast);
}

.patent-card--pro:hover .patent-card__cta i {
  transform: translate(2px, -2px);
}

/* Homepage grid — slightly larger title */
.patents-grid .patent-card__title {
  -webkit-line-clamp: 2;
  font-size: 1rem;
}

.patents-grid .patent-card__cover {
  max-height: 152px;
}

/* Compact catalog density */
.patent-card--compact .patent-card__visual {
  padding: 14px 14px 12px;
}

.patent-card--compact .patent-card__cover {
  max-height: 112px;
}

.patent-card--compact .patent-card__body {
  padding: 14px 14px 16px;
}

.patent-card--compact .patent-card__title {
  font-size: 0.875rem;
  -webkit-line-clamp: 3;
}

/* 仅展示单条专利时居中，避免在宽网格里过窄 */
.patents-grid--solo {
  grid-template-columns: minmax(0, 300px);
  justify-content: center;
}

.patent-grid--solo {
  grid-template-columns: minmax(0, 300px);
  justify-content: center;
}